1. Field of the Invention
This invention relates to a cospun yarn comprising poly(hexamethylene adipamide/caproamide) (nylon 6,6/6) filaments and certain basic dyeable polyester filaments and to a process for making such yarn.
2. Description of the Prior Art
The desirability of cospinning poly(hexamethylene adipamide) and poly(ethylene terephthalate) filaments which may contain basic dye sensitizing units is disclosed in Reese U.S. Pat. No. 3,681,910. Cospun yarn comprising a major amount up to about 70 weight percent of poly(ethylene terephthalate) filaments with the remainder being poly(hexamethylene adipamide) filaments containing 3 to 10 weight percent of an N-alkyl substituted polycarbonamide is described in copending coassigned U.S. application Ser. No. 432,443 filed Oct. 4, 1982. A need for making the polyester component of such cospun yarn basic dyeable prompted efforts to incorporate basic dye sensitizing units into the polyester chain following the teachings of U.S. Pat. No. 3,018,272. It was found however, that attempts to cospin the modified polyester with nylon 6,6 resulted in an intolerable number of mechanical yarn defects. It is an object of this invention to provide a cospun yarn containing the modified polyester and having only a minor proportion of mechanical defects.